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排序方式: 共有752条查询结果,搜索用时 15 毫秒
1.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究 总被引:5,自引:0,他引:5
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。 相似文献
2.
PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed. 相似文献
3.
Bile acid receptors in colorectal cancer 总被引:4,自引:0,他引:4
Bile acids are thought to be involved in both the aetiology and development of colorectal cancer. In this study the existence of specific bile acid receptor proteins has been postulated. A receptor assay which involved labelling with 14C-deoxycholic acid was performed as well as autoradiography using 3H-deoxycholic acid. In an initial study resected colorectal cancer and adjacent histologically normal colorectal mucosa from 39 patients were studied, as were samples of normal gastric mucosa, cancers and benign colorectal tumours. Specific receptors to deoxycholic acid were detected in 12 (30.8 per cent) of the colorectal cancers, but in only 1 (2.6 per cent) of the samples from normal colorectal mucosa (X2 = 11.16, P less than 0.005). No deoxycholic acid receptors were detected in any other tissue studied. Autoradiographs of colorectal cancers showed binding of 3H-deoxycholic acid in receptor-positive tumour tissue. These findings might provide some explanation for the evidence linking bile acids with the disease. 相似文献
4.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice. 相似文献
5.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
6.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
7.
N Summerton 《The British journal of general practice》1997,47(424):748-750
8.
C P Gibbons C B Summerton P G McNally R Kay C B Brown A T Raftery 《Transplantation》1986,41(4):464-467
Postoperative intrarenal pressure measurements may be an aid to the diagnosis of acute renal transplant rejection, especially in patients treated with cyclosporine. Serial measurements of intrarenal pressure were made in 38 recipients using a fine-needle technique. Thirty-two intraoperative and 207 postoperative measurements were made, and 39 clinical rejection episodes (23 confirmed by biopsy) monitored. Intraoperative pressures in grafts with immediate function (37.4 +/- 4.0 mmHg, mean +/- SEM) were not significantly different from those with delayed function (30.9 +/- 4.8 mmHg), whereas postoperative pressures were greater (P less than 0.01) in kidneys with acute tubular necrosis (29.4 +/- 1.9 mmHg) than in functioning grafts (20.4 +/- 0.9 mmHg). Pressures recorded during clinical rejection episodes (44.3 +/- 2.3 mmHg) exceeded (P less than 0.001) those during quiescent periods (23.6 +/- 1.0 mmHg). During rejection episodes, higher pressures (P less than 0.01) were recorded from tender or palpably enlarged grafts (52.5 +/- 3.0 mmHg) than in the absence of these signs (36.3 +/- 3.1 mmHg), and patients whose transplants biopsies showed cellular rejection tended to have greater pressures (50.1 +/- 4.1 mmHg) than those with concomitant vasculopathy (36.4 +/- 3.9 mmHg), but the latter did not reach statistical significance. In 7 cases of cyclosporine toxicity the intrarenal pressure was 17.8 +/- 4.2 mmHg. Using a diagnostic cut off point of 40 mmHg, the investigation failed to recognize 26% of acute rejection episodes--and, in the presence of acute tubular necrosis, it wrongly categorized 21% of nonrejectors. While its predictive capacity was limited, the test may occasionally be helpful in the differentiation of cyclosporine toxicity and rejection in functioning kidneys. 相似文献
9.
10.
BACKGROUND: Growing interest is nowadays focused on the quality of life of
elderly people who survive with chronic diseases. Coronary heart disease
(CHD) is one of the most common diseases among the elderly and may have an
unfavourable impact on the patient's emotional well-being. OBJECTIVES: We
aimed to describe the prevalence of depression and the occurrence of
depressive symptoms among elderly CHD patients, with a special emphasis on
the relations between depression and the severity of CHD, and to find out
the possible association between CHD and depression. METHODS: The study was
carried out at the health centre of the municipality of Lieto, in
south-west Finland. The study population consisted of 488
community-dwelling men and 708 women, over 64 years old, from among whom
the participants with CHD (89 men and 73 women) were selected, and for whom
178 male and 146 female sex- and age- matched controls (free of CHD) were
drawn from the population. CHD patients were selected on the basis of the
presence of angina pectoris or a past myocardial infarction. Depressive
symptoms were measured with the Zung Self-rating Depression Scale.
Depression was described in relation to the severity of dyspnoea and chest
pain among patients. The associations between depression and age, health,
health behaviour, drugs, functional ability and social, psychosocial and
environmental factors were analysed by logistic regression analyses.
RESULTS: The prevalence of depression was 29% among male patients and 20%
among female patients. Depression was significantly more common among male
CHD patients than among male controls (P = 0.011). Among women, depression
was not associated with CHD. Earlier, depression had gone undiagnosed among
many CHD patients and controls, especially male patients. Among male CHD
patients, depression was associated with more severe dyspnoea, but no
similar association was found among female CHD patients. Among men the
occurrence of CHD, physical disability, widowhood or divorce, and among
women previous clinical depression, physical disability and the use of
angiotensin-converting enzyme (ACE) inhibitors, were associated with
depression. CONCLUSION: Depression is common among patients with CHD. It
seems that CHD is not an independent factor in the aetiology of depression
among the elderly. The association of CHD with depression among men is
explained by the acute or chronic psychic stress caused by CHD. It may be
that the more complicated the patient's CHD, the more probable is the
presence of depression.
相似文献